package com.justnow.offer;


import java.math.BigDecimal;
import java.util.Scanner;

/**
 * @author justnow
 * Created on 2020-09-05
 * Description
 *
 *
 * 牛牛班级内有n个男同学和m个女同学
 * 现在老师想要组成一个包含k个同学的合唱队，并且合唱队内至少需要
 * 包含3个男生和4个女生
 * 牛牛想请你帮他设计出一共有多少种不同的方案组合合唱队。因为答案很大，所以，需要取模1000000007

 */
public class Zhongxing02 {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int n = scanner.nextInt(); //男生，至少3个
        int m = scanner.nextInt(); //女生，至少2个
        int k = scanner.nextInt();
        BigDecimal sum = new BigDecimal(0);
        if (n == 3 && m == 2) {
            System.out.println(1);
            return;
        }

        for (int i = 3; i <= n ; i++) {
            for (int j = 2; j <= m; j++) {

                if (i + j == 5) {
                    continue;
                }
                if (i + j == k) {
                    BigDecimal boy = compoent(n, i);
                    BigDecimal girl = compoent(m, j);
                    sum = sum.add(boy.multiply(girl));
                } else {
                    break;
                }
            }
        }
        System.out.println(sum.remainder(new BigDecimal(1000000007)));
    }

    public static BigDecimal compoent(int n, int a) {
        if (n == a)
            return new BigDecimal(1);
        BigDecimal top = new BigDecimal(1);
        BigDecimal down = new BigDecimal(1);
        for (int i = 0; i < a; i++) {
            top = top.multiply(new BigDecimal(n - i));
        }
        for (int i = 1; i <= a ; i++) {
            down = down.multiply(new BigDecimal(i));
        }

        return top.divide(down);
    }
}
